1. Field of the Invention
The present invention relates to a paper feeding system and, in particular, to a paper feeding system with a separator and paper blocking mechanisms.
2. Description of the Prior Art
Business machines are often used in offices to help with the manipulation of documents. These business machines include copiers, fax machines, printers, etc. To facilitate a continuous document process, these business machines all have paper feeding systems to supply paper. Since any business machine can only process one page at a time, the paper feeding system has to be able to send exactly one sheet of paper each time. If the paper feeding system sends out more than one sheet of paper at a time, the sheets are likely to become jammed within the machine, causing delays in the whole printing process, as well as wasting paper. Therefore, it is of great importance to design a paper feeding system that can send out precisely one sheet of paper at a time.
Please refer to FIG. 1, which is a schematic view of a conventional paper feeding system 10. This paper feeding system 10 comprises a paper tray 12, a lift plate 14 rotatably fixed in the paper tray 12, a lift rod 16, and a pick-up roller 18. When the lift rod 16 rotates counterclockwise, the front end of the lift plate 14 will be lifted up so that the pick-up roller 18 contacts the uppermost paper on the lift plate 14 and pushes the paper out of the paper feeding system 10.
Please refer to FIG. 2, which shows the situation when the conventional paper feeding system 10 sends out multiple sheets of paper 11. Since the conventional paper feeding system 10 uses only the pick-up roller 18 to push the paper 11, it is likely that several sheets of paper 11 will be sent out of the paper feeding system 10 at one time because of friction between the sheets of paper. Such multiple paper feedings cause jamming in the machine. This not only wastes paper 11, but can also reduce the lifetime of the machine.
Therefore, it is a primary object of the present invention to provide a paper feeding system with separator and paper blocking mechanisms to solve the above-mentioned problems.
The present invention provides a paper feeding system with a separator and a paper blocking mechanism. The paper feeding system has a housing, and a lift plate installed in the housing for holding paper. The lift plate includes a front end and a rear end, and the rear end is rotatably fixed in the housing. A first elastic device is located under and contacts the front end of the lift plate, and is used to lift up the front end of the lift plate. A pick-up roller is rotatably fixed in the housing above the front end of the lift plate. When the first elastic device lifts up the lift plate, a sheet of paper carried by the lift plate will come into contact with the pick-up roller, and the pick-up roller frictionally engages and moves the uppermost sheet of paper out of the lift plate into a paper feeding path. A depressive device in the housing presses down on the front end of the lift plate. A separator in the housing elastically contacts the lower side of the pick-up roller. A paper blocking mechanism is rotatably fixed in the housing. The paper blocking mechanism is installed ahead of the front end of the lift plate and capable of blocking the paper, preventing the paper from moving forwards and leaving the lift plate. Finally, a driving device drives the pick-up roller and the depressive device. When the driving device drives the depressive device to press down on the front end of the lift plate so that the paper on the lift plate is moved away from the pick-up roller, the lift plate will press the separator and cause the separator to move away from the pick-up roller. The paper blocking mechanism will push the paper backwards to the lift plate, and when the driving device drives the depressive device in the opposite direction, the first elastic device will lift up the front end of the lift plate so that the uppermost sheet of paper on the lift plate contacts the pick-up roller, and the separator will contact the pick-up roller due to the motion of the lift plate. The paper blocking mechanism is pushed away at the same time so that the paper on the lift plate can be moved forwards and leave the lift plate.
It is an advantage of the present invention that the paper separator and paper blocking mechanisms ensure that the automatic paper feeding system delivers only a single sheet of paper at a time.
These and other objectives and advantages of the present invention will no doubt become obvious to those of ordinary skill in the art after having read the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings.